Method of and means for fluidic control



QLHIMJH MUUW! July 15, 1969 J. s. SMITH METHOD OE AND MEANS FOR FLUIDIC CONTROL Filed Jan. 3, 1967 3,455,317 METHOD OF AND MEANS FOR FLUIDIC CONTROL Joseph S. Smith, Williamsville, N.Y., assignor to Houdaille Industries, Inc., Buffalo, N.Y., a corporation of Michigan Filed Jan. 3, 1967, Ser. No. 626,908 Int. Cl. F15c 1/14 U.S. Cl. IS7-81.5 10 Claims ABSTRACT OF THE DISCLOSURE A fluidic stream is controlled by 'bending it from its jet axis by the effect of a control stream in near miss crossing relation thereto.

This invention relates to the art of fluidics, and more particularly concerns a new method of and means for uidic control or switchin lI-Ieretofore, laminar flow jet devices have depended upon the break-up of the laminar main fluid jet stream under the action of a control jet stream. That is, it has been deemed necessary to effect collision of the main laminar stream and a control stream. As a result, such devices have been limited in use to ON-OFF switching.

I have discovered that the main jet stream can be controlled for modulation and switching by bending it without destroying the laminar condition of the stream. This new result is accomplished by directing a control stream in near miss crossing relation to the main stream, namely, by having the control stream crossingly related to the main stream but with the stream axes in narrowly spaced offset relation, such that the control stream has a deflecting-action on the main stream but does not destroy its laminar condition; While I do not have an exact explanation for the fluidic phenomenon I have discovered, it is my opinion that it is the result of boundary layer frictional lproximity relation of the main and control streams; 'and this explanation where Vused herein by way of description and definition should be construed broadly as comprising whatever the actual physics may be that produce the result.

It is, accordingly, an important object of the present invention to prei/ide a new method of and means for controlling a fluidic jet stream.

Another object of the invention is to provide a new method of and means for fluidic switching.

Another object of the invention is to provide a new method of and means for fluidic switching utilizing a control stream but maintaining the laminar integrity of the main jet stream being controlled.

Other objects, features and advantages of the present invention will be readily apparent from the following detailed description taken in conjunction with the accompanying drawing, comprising a single figure schematically illustrative of the new method and means of the preseht invention.

In the drawing, a basic fluidic arrangement illustrative of the. method and means of the present invention has been depicted, and it will be understood that this may be various applied to a wide variety of fluidic device permutations to perform numerous iluidic functions and may readily be incorporated in suitable fluidic modules. A main laminar jet stream S is directed from a supply means comprisng a jet nozzle or orifice which may be simply the exit end of -a main stream supply tube 7 deriving its lluids supply such as a suitable gas, for example, air, or a liquid such as water, from any desirable source and under the desired operating pressure. Normally, and undeflected, the main stream S travels on a straight axis 8 United States Patent O "ce 3,455,317 Patented July 15, 1969 into a receiver comprising an entry mouth 9 on one end of a tube 10 providing an output passage.

According to the present invention, control of the main stream S is effected by means of a control stream CS. Instead of the conventional collision technique employed heretofore, the control stream CS is directed crossingly,A but with its axis 11 offset, `as indicated by the double pronged arrow 12, from the axis 8 of the main stream sogthat the two streams are in a near miss offset crossing relation. To produce the control stream CS means are provided comprising an input orifice 13 which may comprise the end of a tube 14 affording a conduit leading from a suitable control pressure fluid source and under such pressure that the control stream CS issues fromt-he jet device 13 in a condition of laminar flow.

By having the control stream CS in a condition of laminar flow where it crosses with respect to the main stream S, and with the axes 8 and 11 sufliciently offset to avoid turbulent contact of the streams, but in sufliciently close tangency to afford what I prefer to term boundary layer frictional proximity, I effect a bending deflection of the main stream from its normal axial path and about the control stream, as shown. By suitable selection of the crossing angle of the streams, regulation of the control stream pressure, and the like, the degree of such bending deflection can be readily varied to effect modulation of the output stream in the receiver 10 selective splitting of the main stream by shifting it with respect to its entry into the mouth 9 of the receiver, utilizing the rim defining the mouth as the splitting instrumentality.

On the other hand, for switching purposes, the frictional control reaction effected by the pressure of the con trol stream CS is such as to cause sufficient bending of the main stream S to miss the receiver 10 entirely and divert the main stream into means defining a second or switching receiver having an entry mouth 15, offset from the receiver mouth 9 in the same direction as the control stream is offset from the main stream, and located at one end of a tube 17 providing a switching output c'onduit. This result is indicated in the schematic illustration by the full line downwardly deflected position of the main stream S as compared to its normal axial position thereabove shown in dash outline. Although only one of the secondary or switching receivers is shown, it will be appreciated that a plurality of such receivers located in the swinging arc of controlled deflection of the main stream from its normal axial position to the maximumI deflected position, while maintaining its laminar integrity, may be provided for multiple switching purposes.

Many other switching arrangements will readily be apparent such, for example, as by having a plurality of control stream orifices selectively operable to produce control streams for deflecting the main stream in selectively different directions to enter selected switching receivers located in a suitable cluster about the primary output receiver.

In a typical simple fluidic switch arrangement utilizing the specific disclosure, the main stream jet 5 has been of 10 to 20 inch water gauge. The distance between the jet about .060 inch diameter, with a fluid pressure of about 5 and the receiver mouth 9 has been from 1 to 11/2 inch, and the deflection obtained by the control stream supplied by the jet 13 also of .060 inch in diameter and extending generally normal to but with its axis 11 offset from the axis 8 on the order of 11/2 times the jet diameter has been between 10 and 15 from the axis `8. Of course, it will be apparent that numerous variations are obtainable by selection of the various parameters.

It will be understood that variations and modifications may be effected without departing from the spirit and scope of the novel concepts of this invention.

ieu w e I claim as my invention: 1. A method of uidic control comprising:

directing a substantially laminar main fluid s tream from a supply device toward a spaced concentrically arranged output receiver;

and directing a substantially laminar control stream in cross near miss offset boundary layer frictional proximity relation to said main stream and thereby effecting -a bending deflection of said main stream about said control stream.

2. A method as defined in claim 1, including receiving the bent main stream in a second receiver.

3. A method as defined in clainr 1, in which the streams are produced by jets of the same diameter, and the Spacing between the axes of the streams is on the order of 11/2 times the jet diameter.

4. A method as defined in claim 1, according to which the degree of deflection of the main stream is selectively predetermined by the pressure of the control stream. l

5. A method as defined in clairrr 1, in which the streams are provided by respective jets on the order of .O6`inch in diameter, the pressure of the control stream is between ten and twenty inch water gauge, the spacingdistance is between 1 and lVz inches, and the offset relationship of the axes of the streams is on the order of 11/2 times the jet diameter. i

6. A iluidic control device comprising:

a supply device having an outlet for producing a substantially laminar main iluid stream; an output receiver coaxially aligned in spaced relation to the supply device outlet; p

and meansproviding a substantially laminar control fluid stream related to saidY supply device and said output receiver to direct the control stream in crossing near miss oti'set boundary layer frictional proximity to said main stream for effecting a'bending deflection of said main stream about said control stream.

7. A device as defined in claim 6, including a second switching receiver having an entry mouth adjacent to said output receiver and ofset therefrom in the same direction as said control stream and receptive of the deected main stream.

8. A device as defined in claim 6, in which the supply device and the control stream means have respective jet orifices of common diameter, and the axes of the orifices are so related that the axes of the main stream and the control stream are offset at their point of nearest proximity on the order of 11/2 times the jet diameter.

9. A device as defined in claim 7, in which the second receiver is located with an entry mouth 10 to 15 from the main stream axis.

10. A device as defined in claim 6, in which the supply device and the control stream means have respective jets on the order 4of .06 inch diameter, the distance between the jets is on the order of 1 to 1'1/2 inches, and the offset relationship of the streams is a distance at the point of nearest proximity of about 1`1/z times the orifice diameter between the stream axes.

References Cited UNITED STATES PATENTS 9/1965 Zilberfarb 137-815 2/1966 Auger 137-815 

